In a link chain according to DE-U 77 37 243 the adapter foot is secured in the hollow bolt by means of a safety cap provided with claws, which is slipped onto the projecting insertion end of the adapter foot. The safety cap is an element which can be manufactured and made available separately, for whose disassembly a tool is required and which can no longer be used after having been disassembled.
The adapter foot forms a hinge bolt of the chain in a link chain known from DE-U 71 30 659. A split-pin is inserted into the projecting insertion end of the adapter foot for securing. This is an element which can be manufactured and made available separately in the assembly of the of the adapter.
In a hollow bolt link chain known from DE-A-22 34 115 the insertion end of the adapter foot projecting beyond the hollow bolt is expanded by means of cold forming. The assembly of the adapter is time-consuming and requires special tools. After its disassembly, the adapter foot can no longer be used or can only be used after subsequent processing.
In a hollow bolt link chain for a conveyor device known from DE-U 76 10 413 the adapter foot is formed at the carrier. The securing is effected by means of a claw ring in a circumferential groove in the insertion end. A compression sleeve is pressed onto the adapter foot at the opposite side as a counter-stop. The assembly is time-consuming. A special tool is used for disassembly. The claw ring can only be used once. The adapter is multi-partite.
It is known from DE-A 28 14 956 to construct the hinge bolts in extended fashion in a link chain for a conveyor device. The adapter is a sleeve, preferably a sleeve with a longitudinal slot, which is pressed onto the projecting end of the hinge bolt and into which the carrier is pressed. The assembly and disassembly is troublesome. The frictional mounting of the sleeve involves the risk of an uncontrolled loosening or falling off of the sleeve. The additional expenditure during the manufacturing of the chain with the extended hinge bolt is great.
In a conveyor chain made of plastic components, which is known from U.S. Pat. No. 4,950,398 the adapter is fixed by means of two pins inserted into the hollow bolts and secured by means of split-pins inserted from the outside. The hollow bolts are fixed in the chain by means of a locking which is possible due to the deformability of the plastic material. A locking ring is formed at the inside of a bore of a formed sleeve of an exterior bracket, which locks in a locking groove at the outside at the end of the hollow bolt.
The adapter foot is a journal in a hollow bolt link chain known from U.S. Pat. No. 4,518,077, which is passed through the hollow bolt and is locked with a front end having a locking groove in a locking recess of the side plate of the opposite adapter. Two sides plates at both sides of the chain are always required, even if only one carrier must be attached to one side. Carriers are well known in the prior art, as is indicated in U.S. Pat. No. 4,518,077, which is incorporated herein by reference.
In a conveyor chain known from U.S. Pat. No. 4,927,002, which comprises carriers attached to one chain side, each adapter foot is a short hollow shaft end which is slipped onto the extended end of the pivot with a press fit. This securing of the adapter which is only frictional can get detached during operation of the conveyor chain. Carriers are well known in the prior art, as is further indicated in U.S. Pat. No. 4,927,002, which is incorporated herein by reference.
An adapter element known from DE-A-26 13 118 consists of a counterplate with two pins firmly affixed thereto, at whose ends circumferential grooves are formed. The pins are inserted through the hollow bolts from the side of the chain opposite to the carrier until they project at the other side. The adapter is slipped on with sleeves fitting onto the projecting pin ends and has a tongue projecting transversely downwards, which engages in the circumferential grooves.
In a chain known from DE-U-88 02 417 each carrier bolt is provided with an external thread with which it is screwed into an inner thread of the hollow bolt.
In a segmental belt consisting of interlocking segments, which is known from U.S. Pat. No. 5,174,438, each hinge bolt locks into recesses in link projections of the segments.
In a chain known from DE-C-17 81 377 a carrier means is affixed to the hinge bolt, which is riveted at both ends.
A connection element of two chains, which is known from DE-A-27 14 273, is slipped onto projecting pivots of the chain. The connection element is secured in its position by a transverse bar connecting both chains.
In a link chain known from FR-A-25 54 797 an adapter element is slipped from above with claws onto the sleeves of the chain and between the link plates.
In a chain known from FR-A-26 03 260 a support for carrier components is slipped onto the extended hinge bolts of the chain from above and locked positively. The support grips over the chain at both sides.
The invention is based on the object of providing a hollow bolt link chain of the type mentioned at the beginning and an adapter for affixing a carrier at such a link chain, in which as few elements as possible are used for the pull-out protection of the adapter foot, in which the adapter foot can be re-used and optionally relocated and in which no special tool is required for assembly and disassembly.